Common Oxidation States

Q.

What is the oxidation number of H in ${\mathrm{AlH}}_3$?

Q. What is the oxidation state and covalency of Al in [AlCl(H2O)5]2+

Q.

What is the oxidation number of $\mathrm{Li}$ in ${\mathrm{LiAlH}}_4$?

Q. Which of the following will not under go disproportionation reaction in the presence of dilute (or) Conc NaOH

1. P₄

2. S₈

3. Cl₂

4. F₂

Q. An element which never has a positive oxidation number in any of its compounds

1. Fluorine
2. Oxygen
3. Chlorine
4. Boron

Q. What is the oxidation states of C5, Fe3, Cl2, Br3, H2 in the compounds Na2S2O3, C5O5, Fe3O4, CaOCl2, Br3O8, H2S2O8?

Q. Which of the following lanthanoids show +2 oxidation state besides the characteristic oxidation state +3 of lanthanoids?

1. Ce
2. Eu
3. Yb
4. Ho

Q. How fluorine shows +1 oxidation state in HOF

Q.

Of the four oxyacids of chlorine the strongest oxidising agent in dilute aqueous solution is

1. HClO₄

2. HClO₃

3. HClO₂

4. HOCl

Q.

When $KMn{O}_4$ acts as an oxidising agent and ultimately forms $[Mn{O}_4{]}^{2-}$ ,
$Mn{O}_2$ _, $M{n}_2{O}_3$, $[Mn{]}^{2+}$ , then the number of electrons transferred in each case respectively is

1. 4, 3, 1, 5

2. 1, 5, 3, 7

3. 1, 3, 4, 5

4. 3, 5, 7, 1

Q. Calculate the Oxiidation Number of atoms in the compounds
a) NaAuCl4
b) OF2
c) NH2OH
d) Ca(ClO2)2

Q. In which of the following compound transition metal has zero oxidation state

1. $N{H}_{2}N{H}_2$
2. $NOCl{O}_4$
3. $\left[Fe\right(CO{)}_5]$
4. $Cr{O}_5$

Q. In all of its compounds Oxidation state of oxygen may vary from

Q. Oxidation states of the metal in the minerals haematite and magnetite, respectively, are
(IIT-JEE, 2011)

1. II, III in haematite and II in magnetite
2. II, III in haematite and III in magnetite
3. II in haematite and II, III in magnetite
4. III in haematite and II, III in magnetite

Q. What is the oxidation number of chlorine in bleaching powder

Q. In acidic medium, $H_2{O}_2$ changes $C{r}_2{O}_7^{2-}$ to $Cr{O}_5$ which has two ( - O - O -) bonds. Oxidation state of Cr in $Cr{O}_5$ is

1. 5
2. 3
3. 6
4. -10